Integrated Design and Reproducible Feasibility Analysis of a Four-Wheel Rover with Packet-Commanded Imaging, LiDAR Ranging, and Learning-Assisted Target Recognition
Organizations: BAF Shaheen College Kurmitola · St. Joseph Higher Secondary School · Dhaka Residential Model College · South Point School & College
Abstract
This study develops an integrated, reproducible design assessment for a four-wheel educational rover intended for the high-school remote-control division of the 2027 NASA Human Exploration Rover Challenge. The architecture combines commercial differential drive control, independently sprung wheel carriers, separate drive and task batteries, and a Raspberry Pi-based subsystem that executes received imaging and ranging commands. The analysis reconciles component lists with dimensioned computer-aided design views, derives mobility and electrical constraints, and connects sensor geometry to command execution. At the estimated mass of 10.919 kg, a 215 mm wheel rotating at 200 RPM produces a theoretical rolling speed of 8.105 km/h; consequently, the nominal motor label does not establish compliance with an 8 km/h design ceiling. A steady 20-degree climb requires at least 1.255 newton-meters per wheel under an assumed rolling-resistance coefficient of 0.10 and equal torque sharing. At 50 ft, an ideal 12-inch feature spans approximately 71 pixels across a full-resolution Camera Module 3 Standard image, while a 1-degree pointing error displaces the ranging ray by approximately 266 mm. An executed synthetic benchmark compares color-geometry rules and two linear support-vector classifiers on 2,400 generated board crops with scene-disjoint evaluation. A separate reference command executor is checked using mocked hardware. These software results and analytical sensitivities support a testable development plan; the study does not report physical rover trials. The principal contribution is a traceable connection between component choices, failure mechanisms, quantitative design limits, and reproducible verification tasks.
Figures & tables
| Quantity | Adopted value or interpretation | Evidence status |
|---|---|---|
| Overall length × width | 655 × 630 mm | Supplied design dimensions |
| Height to camera top | 421 mm, antenna excluded | Supplied design dimension |
| Wheels | Four; 215 mm diameter × 90 mm width | Supplied design dimensions |
| Rim / tire radial thickness | 188 mm / 13.5 mm | Dimension closure verified |
| Estimated fully equipped mass | 10.919 kg | Team-supplied theoretical estimate; unweighed |
| Track / wheelbase | 540 / 440 mm | Conditional inference from outer dimensions |
| Handbook consideration | Design interpretation | Evidence needed before acceptance |
|---|---|---|
| Excursion-ready cube, Rule 5.5.4 | 762 mm on each axis | Measure complete rover, including antenna |
| High-school manufacture, Rule 6.4.2.1 | Team-designed/manufactured chassis, wheels and tires; permitted commercial drive/suspension parts | Manufacturing records and final configuration |
| Primary drive control, Rule 6.4.3 | Commercial transmitter, receiver and ESC control | Demonstration of configured control and failsafe |
| Speed, Rule 6.4.4 | Use 8 km/h as the conservative ceiling associated with the stated 5 mph limit | Full-charge maximum-speed test and limiter verification |
| Mass, Rules 6.4.5 and Section 8.2 | 60 lb absolute limit; 20 lb is a scoring objective | Weigh excursion-ready vehicle |
| Battery protection, Rules 6.4.6–6.4.7 | Separate insulated enclosures; main overcurrent protection | Wiring and enclosure inspection |
| Slope | Required total force (N) | Wheel-output torque per wheel (N·m) | Minimum friction coefficient |
|---|---|---|---|
| 0° | 10.708 | 0.288 | 0.100 |
| 10° | 29.139 | 0.783 | 0.276 |
| 15° | 38.057 | 1.023 | 0.368 |
| 20° | 46.685 | 1.255 | 0.464 |
| 25° | 54.958 | 1.477 | 0.566 |
| 30° | 62.813 | 1.688 | 0.677 |
| Task branch | Illustrative output power (W) | Calculated battery-side current (A) | Proposed input fuse (A) |
|---|---|---|---|
| Pi and USB branch | 25.75 | 2.885 | 5 |
| Pan-servo branch | 15.00 | 1.681 | 3 |
| LiDAR branch | 2.00 | 0.224 | 1 |
| Tilt-servo branch | 5.20 | 0.583 | 1 |
| Total | 47.95 | 5.373 | 7.5 main |
| Token | Required operation represented in the executor | State consequence |
|---|---|---|
| AAA | Begin a task sequence | Open a new record after successful initialization |
| B / C | Turn field of view 30° right / left | Update pan only after successful motion |
| D | Capture and save a new photograph | Use current filter; attach capture date/time |
| E / F | Select red / blue filter | Replace the prior filter selection |
| G | Select no filter | Restore normal-color output |
| H | Measure target distance | Record a fresh, valid result in feet |
| Range | Angular width of a 12-inch feature | Full 4608-pixel width estimate | Same full view scaled to 1920 pixels |
|---|---|---|---|
| 10 ft | 5.725° | 354.78 px | 147.83 px |
| 25 ft | 2.292° | 141.91 px | 59.13 px |
| 50 ft | 1.146° | 70.96 px | 29.57 px |
| Split | Scene groups | Images | Purpose |
|---|---|---|---|
| Training | 300 | 1,200 | Fit feature standardization and SVM parameters |
| Validation | 100 | 400 | Select declared hyperparameters |
| Nominal test | 100 | 400 | Evaluate unseen scenes from nominal generator ranges |
| Shifted test | 100 | 400 | Evaluate altered backgrounds and stronger corruptions |
| Nuisance parameter | Nominal range | Shifted range |
|---|---|---|
| Board width / image width | 0.72–0.88 | 0.64–0.83 |
| Rotation | 30° to +30° | 55° to +55° |
| Per-corner projective jitter | ±0.045 image widths | ±0.10 image widths |
| Exposure multiplier | 0.72–1.20 | 0.38–1.40 |
| Per-channel gain | 0.85–1.15 | 0.58–1.40 |
| Blur standard deviation | 0–0.65 output pixels | 0.65–1.65 output pixels |
| Method | Nominal accuracy | Nominal macro-F1 | Shifted accuracy | Shifted macro-F1 |
|---|---|---|---|---|
| HSV + geometry | 95.00% | 0.9512 | 71.75% | 0.7343 |
| HSV histogram + SVM | 82.00% | 0.7892 | 61.75% | 0.5838 |
| HOG + HSV + SVM | 82.00% | 0.7890 | 48.50% | 0.4784 |
| Subsystem | Verification activity | Record needed | Current status |
|---|---|---|---|
| Envelope and mass | Measure fully equipped rover, including antenna | Dimension sheet and scale record | CAD dimensions and mass estimate only |
| Propulsion | Full-charge speed, sustained climb, repeated turns, stop/failsafe | Speed, current, temperature, stop behavior | Analytical scenarios only |
| Suspension | Loaded corner force–travel and articulation checks | Motion ratios, end stops, corner weights | CAD concept and sensitivity model |
| Printed wheels | Coupon, hub, tire/interface and repeated-load tests | Process settings, forces, displacement, damage | Literature-informed test plan |
| Task power | Concurrent camera, display and servo operation | Rail voltage, pack current, temperature | Energy/current scenarios only |
| RF reception | Complete sequence with motors and converters operating | Received packets, errors, queue timestamps | Architecture and adapter contract |